Electromagnetic relay



July 18, 1961 s. E. E. JOHANNESSON 2,993,151

ELECTROMAGNETIC RELAY Filed Feb. 3, 1959 2 Sheets-Sheet 1 July 18, 1961s. E. E. JOHANNESSON ELECTROMAGNETIC RELAY 2 Sheets-Sheet 2 Filed Feb.5, 1959 fVVE/VTOR SIIEN fit/c El HLD Jc v/MA/A IJJOA' Haw M HfTQR VEYSPatented July 18, 1961 2,993,151 ELECTROMAGNETIC RELAY Sven Eric Evald Johannesson, Hagersten, Sweden, assignor to Telefonaktiebolaget L MEricsson, Stockholm, Sweden, a corporation of Sweden Filed Feb. 3, 1959,Ser. No. 790,947 Claims priority, application Sweden Mar. 7, 1958 6Claims. (Cl. 317-198) The present invention refers to electromagneticrelays and especially to relays of this kind, which have a U-shapedmagnetic circuit including one shank surrounded by the relay coil. Theobject of the invention is to provide a suitable device for supportingthe armature. This is achieved according to the invention by thearmature being provided with a supporting device, which extends alongmost of the second shank of the magnetic circuit.

The invention will be described more in detail in connection to theenclosed drawings. FIG. 1 is a perspective view of the relay. FIG. 2shows a perspective view of the magnetic circuit and the armature. FIG.3 is a terminal view of FIG. 1 and FIG. 4 a left hand side view of FIG.1, which shows the contact springs.

In the relay shown on the drawing the magnetic circuit consists of aU-shaped iron core 11, 12, the one shank 11 of which is surrounded by acoil 13 and the other shank 12 of which is the supporting device of thearmature 14, 15. The iron core and the armature are mounted in a frameof insulating material. This frame is produced in one piece, two flanges16, 17 being connected -by a tubular part, on which the wire is wound.In one of these flanges 16 three contact springs 18, 19, 20 arefastened. The two outer ones of these springs 18, 20 engage at theirfree ends supports 21, 22 formed on the other flange 17. At the flange16 there are also terminals 23, 24 for connecting the two ends of coil13.

The assembly of the relay is made in such a way that the contact springs18, 19, 20 are mounted and the armature 14, 15 is placed on its place inthe frame, and afterwards the iron core 11, 12 is inserted. As is shownin FIG. 2, the armature is L-shaped and consists in the shown example ofa long, narrow part 14 and a wide, short part 15, extending at a rightangle from the first mentioned part. At the place, where the extendedannature-support begins, that is at the junction between the narrow part14 and the wide part, the part 14 is provided with a notch 25. At theother end of the armature-support there is a pin 26. The notch and thepin fit in corresponding parts at the flanges 17, 16. Thus, as soon asthe core has been placed, the armature will be held in position. It willbe supported with its whole narrow, long part and with the one end ofthe wide part 15 on shank 12 of the core, practically along the lengthof its whole shank. The other free end of the wide armature part 15 isprovided with two tabs 27, 28 engaging both sides of the free end of theintermediate contact spring 19. As a result the armature will be kept bythe spring 19* in the position shown in FIG. 3 owing to bias tension inthis spring in relation to the shank 11. When the relay is magnetized byenergizing coil 13, the armature part 15 turns like a one-armed leverabout its support along the shank :12, until it presses against theshank 11. Thereby the contact between the springs 18, 19 is broken and acontact between the springs 19, 20 is closed. When coil 13 isdeenergized, the armature returns into the position shown in FIG. 3.

Due to the support of the armature along almost the whole part of theshank 12 the magnetic losses of the magnetic circuit are small. Theselosses are reduced tin-theiby the shank .12 being provided by such aflattening along its support, that the armature after closing will havea large contact surface against the core. For similar reasons the othershank is also bevelled along the part, which the armature will approach.

As a result of the shown construction a relay has been obtained, whichis entirely wthout screws and screwed details. The armature is kept onits place of the relay core, and it can be locked for instance by makingit somewhat thicker than the recess of flange 16, so that this recess issubjected to a small plastic deformation, when the core is inserted. Therelay construction suggested according to the invention is speciallysuited for small relays and especially for relays intended to be used inprinted circuits. Therefore the terminals 23, 24 and the back ends ofthe contact springs are specially shaped to fit in printed circuits andetched connections.

I claim:

1. An electromagnetic relay comprising a U-shaped core having twostraight parallel shanks, an exciting coil surrounding one of saidshanks, and an armature having an elongated portion lying lengthwiseadjacent to said other shank parallel therewith and another portionextending toward said one shank, said armature being pivotal about alongitudinal axis of said elongated armature portion for attraction ofthe other armature portion toward said one shank in response toenergization of the coil thereon.

2. An electromagnetic relay comprising a U-shaped core having twostraight parallel shanks, an exciting coil surrounding one of saidshanks, and an armature having an elongated narrow arm and a shorterwide arm laterally extending from said narrow arm, and mounting meanssupporting the narrow arm lengthwise adjacent to and parallel with theother shank and pivotal about a longitudinal axis, said wide armextending toward said one shank for magnetic attraction thereby inresponse to an energization of said coil.

3. A relay according to claim 2 wherein said mounting means comprises asupport frame of insulation material, one end of said narrow arm andsaid frame being formed with a pivot pin and a recess respectivelyengaging each other and an intermediate portion of said narrow arm andsaid frame being formed with a lug and a second recess engaging eachother to retain the armature on said other core shank.

4. A relay according to claim 1 wherein said other core shank and saidelongated armature portion have flattened surfaces positioned to faceand engage each other in the attracted position of the armature toprovide for a maximum magnetic flux path between the core and thearmature.

5. An electromagnetic relay comprising a U-shaped core having twostraight parallel shanks, an exciting coil surrounding one of saidshanks, and a substantially L- shaped armature, the long L-arm of saidarmature being of a length substantially equal to that of the othershank, and mounting means supporting said long L-arm lengthwise adjacentto and parallel with said other shank and pivotal about a longitudinalaxis, the short L-arm extending toward said one shank for magneticattraction thereby in response to energization of said coil.

6. A relay according to claim 5 wherein the width of the long L-arm isnarrower than that of the short L-arm.

Horman Jan. 15, 1 957 Pettersson et a1. Oct. 28, 1958

